Upper respiratory tract infections generally require a combination of symptoms and signs.
Symptoms of upper respiratory tract infection include runny nose, nasal congestion, cough and sore throat. Nasopharyngeal congestion, congested mucous membranes and enlarged tonsils are usually present in the physical examination.
Upper respiratory tract infections usually do not have a cough, shortness of breath or chest pain, there is no rales on physical examination, there is no decreased or absent breath sounds, and chest x-rays are all normal.
If the upper respiratory tract infection is caused by bacteria, the routine blood test can show that the white blood cells or neutrophils are increased, and if it is caused by viruses, the routine blood test can show that it is normal, or there are lymphocytes increased.
Clinically, it is often based on these signs and symptoms, combined with blood tests and chest radiographs, to comprehensively determine whether the patient has an upper respiratory tract infection.